Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
10 result(s) for "Wun, Kelly"
Sort by:
Microbiota control acute arterial inflammation and neointimal hyperplasia development after arterial injury
The microbiome has a functional role in a number of inflammatory processes and disease states. While neointimal hyperplasia development has been linked to inflammation, a direct role of the microbiota in neointimal hyperplasia has not yet been established. Germ-free (GF) mice are an invaluable model for studying causative links between commensal organisms and the host. We hypothesized that GF mice would exhibit altered neointimal hyperplasia following carotid ligation compared to conventionally raised (CONV-R) mice. Twenty-week-old male C57BL/6 GF mice underwent left carotid ligation under sterile conditions. Maintenance of sterility was assessed by cultivation and 16S rRNA qPCR of stool. Neointimal hyperplasia was assessed by morphometric and histologic analysis of arterial sections after 28 days. Local arterial cell proliferation and inflammation was assessed by immunofluorescence for Ki67 and inflammatory cell markers at five days. Systemic inflammation was assessed by multiplex immunoassays of serum. CONV-R mice treated in the same manner served as the control cohort. GF and CONV-R mice were compared using standard statistical methods. All GF mice remained sterile during the entire study period. Twenty-eight days after carotid ligation, CONV-R mice had significantly more neointimal hyperplasia development compared to GF mice, as assessed by intima area, media area, intima+media area, and intima area/(intima+media) area. The collagen content of the neointimal lesions appeared qualitatively similar on Masson's trichrome staining. There was significantly reduced Ki67 immunoreactivity in the media and adventitia of GF carotid arteries 5 days after ligation. GF mice also had increased arterial infiltration of anti-inflammatory M2 macrophages compared to CONV-R mouse arteries and a reduced proportion of mature neutrophils. GF mice had significantly reduced serum IFN-γ-inducible protein (IP)-10 and MIP-2 5 days after carotid ligation, suggesting a reduced systemic inflammatory response. GF mice have attenuated neointimal hyperplasia development compared to CONV-R mice, which is likely related to altered kinetics of wound healing and acute inflammation. Recognizing the role of commensals in the regulation of arterial remodeling will provide a deeper understanding of the pathophysiology of restenosis and support strategies to treat or reduce restenosis risk by manipulating microbiota.
Vancomycin treatment and butyrate supplementation modulate gut microbe composition and severity of neointimal hyperplasia after arterial injury
Gut microbial metabolites are increasingly recognized as determinants of health and disease. However, whether host–microbe crosstalk influences peripheral arteries is not understood. Neointimal hyperplasia, a proliferative and inflammatory response to arterial injury, frequently limits the long‐term benefits of cardiovascular interventions such as angioplasty, stenting, and bypass surgery. Our goal is to assess the effect of butyrate, one of the principal short chain fatty acids produced by microbial fermentation of dietary fiber, on neointimal hyperplasia development after angioplasty. Treatment of male Lewis Inbred rats with oral vancomycin for 4 weeks changed the composition of gut microbes as assessed by 16S rRNA‐based taxonomic profiling and decreased the concentration of circulating butyrate by 69%. In addition, rats treated with oral vancomycin had exacerbated neointimal hyperplasia development after carotid angioplasty. Oral supplementation of butyrate reversed these changes. Butyrate also inhibited vascular smooth muscle cell proliferation, migration, and cell cycle progression in a dose‐dependent manner in vitro. Our results suggest for the first time that gut microbial composition is associated with the severity of arterial remodeling after injury, potentially through an inhibitory effect of butyrate on VSMC. This report demonstrates that antibiotic modulation of gut microbial composition alters production of a microbe‐derived metabolite, sodium butyrate, which then regulates the arterial remodeling response after balloon angioplasty in rats. One potential mechanism is inhibition of vascular smooth muscle cell proliferation, migration, and cell cycle progression by butyrate.
Pathological findings following radical prostatectomy in patients who are candidates for active surveillance: impact of varying PSA levels
Active surveillance is an acceptable treatment option in men with a low-risk prostate cancer. In the present study, we have retrospectively reviewed the outcomes of 509 men who fit the criteria for active surveillance but selected radical prostatectomy. Then, the impact of varying prostate-specific antigen (PSA) levels on the risk of upstaging and upgrading in these patients was assessed. Pathological characteristics of patients who fulfilled the inclusion criteria under three active surveillance criteria--those of the University of California-San Francisco, the National Cancer Institute and the European Association of Urology--were examined. The proportion of men who were deemed candidates for active surveillance but were subsequently upstaged or upgraded was determined. Of 509 patients, 186 (36.5%), 132 (25.9%) and 88 (17.3%) men fulfilled the active surveillance criteria, respectively. Upgrading (Gleason scores 7-10) ranged from 32.8% to 38.6%, while upstaging (≥ pT3) ranged from 10.2% to 12.5%, depending on the three active surveillance criteria. After a median follow-up of 24 months, three patients developed a biochemical recurrence. When the impact of varying PSA levels was examined using a test for trend analysis in the context of PSA for each protocol, rates of upstaging were lower in men with PSA 〈4 ng m1-1. However, there was no impact of varying PSA levels on upgrading. In conclusion, commonly used active surveillance protocols carry the risks of upgrading and upstaging. More reliable and accurate markers are needed to better stratify the risks of men who are appropriate candidates for active surveillance.
Pathology of congenital Zika syndrome in Brazil: a case series
Zika virus is an arthropod-borne virus that is a member of the family Flaviviridae transmitted mainly by mosquitoes of the genus Aedes. Although usually asymptomatic, infection can result in a mild and self-limiting illness characterised by fever, rash, arthralgia, and conjunctivitis. An increase in the number of children born with microcephaly was noted in 2015 in regions of Brazil with high transmission of Zika virus. More recently, evidence has been accumulating supporting a link between Zika virus and microcephaly. Here, we describe findings from three fatal cases and two spontaneous abortions associated with Zika virus infection. In this case series, formalin-fixed paraffin-embedded tissue samples from five cases, including two newborn babies with microcephaly and severe arthrogryposis who died shortly after birth, one 2-month-old baby, and two placentas from spontaneous abortions, from Brazil were submitted to the Infectious Diseases Pathology Branch at the US Centers for Disease Control and Prevention (Atlanta, GA, USA) between December, 2015, and March, 2016. Specimens were assessed by histopathological examination, immunohistochemical assays using a mouse anti-Zika virus antibody, and RT-PCR assays targeting the NS5 and envelope genes. Amplicons of RT-PCR positive cases were sequenced for characterisation of strains. Viral antigens were localised to glial cells and neurons and associated with microcalcifications in all three fatal cases with microcephaly. Antigens were also seen in chorionic villi of one of the first trimester placentas. Tissues from all five cases were positive for Zika virus RNA by RT-PCR, and sequence analyses showed highest identities with Zika virus strains isolated from Brazil during 2015. These findings provide strong evidence of a link between Zika virus infection and different congenital central nervous system malformations, including microcephaly as well as arthrogryposis and spontaneous abortions. None.
T cell autoreactivity directed toward CD1c itself rather than toward carried self lipids
The hallmark function of αβ T cell antigen receptors (TCRs) involves the highly specific co-recognition of a major histocompatibility complex molecule and its carried peptide. However, the molecular basis of the interactions of TCRs with the lipid antigen–presenting molecule CD1c is unknown. We identified frequent staining of human T cells with CD1c tetramers across numerous subjects. Whereas TCRs typically show high specificity for antigen, both tetramer binding and autoreactivity occurred with CD1c in complex with numerous, chemically diverse self lipids. Such extreme polyspecificity was attributable to binding of the TCR over the closed surface of CD1c, with the TCR covering the portal where lipids normally protrude. The TCR essentially failed to contact lipids because they were fully seated within CD1c. These data demonstrate the sequestration of lipids within CD1c as a mechanism of autoreactivity and point to small lipid size as a determinant of autoreactive T cell responses. CD1 molecules present diverse lipid ligands to TCRs expressed by NKT cells. Rossjohn, Moody and colleagues show a unique form of autoreactivity with human CD1c molecules, whereby TCRs recognize a closed conformation of CD1c molecules, which are loaded with a diverse array of ‘headless’ glycolipids.
Evidence of Zika Virus Infection in Brain and Placental Tissues from Two Congenitally Infected Newborns and Two Fetal Losses — Brazil, 2015
Zika virus is a mosquito-borne flavivirus that is related to dengue virus and transmitted primarily by Aedes aegypti mosquitoes, with humans acting as the principal amplifying host during outbreaks. Zika virus was first reported in Brazil in May 2015. Here, Martines et al describe evidence of a link between Zika virus infection and microcephaly and fetal demise through detection of viral RNA and antigens in brain tissues from two congenitally infected newborns and two fetal losses reported in the country in 2015.
Effect of capacity-building in infectious disease on mortality among children under-5: a cluster randomised trial
Due to shortage of health personnel in sub-Saharan Africa, WHO advocates shifting some tasks traditionally performed by doctors to mid-level practitioners (MLPs). The effect on under-5 (U5) mortality of an on-site support (OSS) intervention for MLPs after an Integrated Management of Infectious Disease training programme was estimated. 36 health centres were randomised 1:1 to staggered implementation arms, with the intervention group receiving OSS during phase 1 (April to December, 2010) and both groups receiving OSS during phase 2 (March to October, 2011). Mortality was assessed by a household survey employing a novel sampling design; 300 enumeration areas (EAs) per arm were randomly selected among all within 5 km of the health centres. Key informants assisted in identifying all households with a U5 death in each EA for interviews. A random sample of 30 households was also selected for interviews to provide denominator person-time information. Birth histories were collected from all female residents aged 15–49 years or proxies, and survival data were collected on children whose mothers were not residents. Mortality risk was compared in intervention and control arms during baseline (August, 2008, to March, 2010), phase 1, and phase 2 using discrete-time survival analysis. A total of 87 189 households in 597 EAs were listed; 20 546 were selected; and 17% reported a U5 death. For 68% of children in the sample, their resident birth mother was interviewed. During phase 1, unadjusted odds of death were 1·09 (95% CI 0·81–1·39) times higher than baseline in the intervention arm and 1·23 (1·05–1·46) in the control. During phase 2, odds rose to 1·77 (1·31–2·40) times higher than baseline in the intervention arm and 1·67 (1·42–1·97) in the control. Adjusted results were similar. Differences between arms were not statistically significant during any time period. U5 mortality increased in both arms, but timing of the increase was delayed in the OSS arm during intervention. The Infectious Disease Capacity Building Evaluation (IDCAP) was funded by grant 49298 to Accordia Global Health Foundation from the Bill & Melinda Gates Foundation.
Notes from the Field : Evidence of Zika Virus Infection in Brain and Placental Tissues from Two Congenitally Infected Newborns and Two Fetal Losses — Brazil, 2015
Zika virus is a mosquito-borne flavivirus that is related to dengue virus and transmitted primarily by Aedes aegypti mosquitoes, with humans acting as the principal amplifying host during outbreaks. Zika virus was first reported in Brazil in May 2015 (1). By February 9, 2016, local transmission of infection had been reported in 26 countries or territories in the Americas.* Infection is usually asymptomatic, and, when symptoms are present, typically results in mild and self-limited illness with symptoms including fever, rash, arthralgia, and conjunctivitis. However, a surge in the number of children born with microcephaly was noted in regions of Brazil with a high prevalence of suspected Zika virus disease cases. More than 4,700 suspected cases of microcephaly were reported from mid-2015 through January 2016, although additional investigations might eventually result in a revised lower number (2). In response, the Brazil Ministry of Health established a task force to further investigate possible connections between the virus and brain anomalies in infants (3).